Method for Detecting a Crack in a Semiconductor Body of a Semiconductor Component

Abstract

A semiconductor component includes a semiconductor body having a bottom side, a top side spaced distant from the bottom side in a vertical direction, and a thickness in the vertical direction, and a crack sensor configured to detect a crack in the semiconductor body. The crack sensor extends into the semiconductor body. A distance between the crack sensor and the bottom side is less than the thickness of the semiconductor body. A crack in the semiconductor body is detected by specifying a first value of a characteristic variable of the crack sensor, determining a second value of the characteristic variable of the crack sensor at a different time than the first value is specified, and determining the semiconductor body has a crack if the second value differs from the first value by more than a pre-defined difference.

What is claimed is: 
     
         1 . A method for detecting a crack in a semiconductor body of a semiconductor component, the method comprising:
 providing a semiconductor component with:
 a semiconductor body having a bottom side, a top side spaced distant from the bottom side in a vertical direction, and a thickness in the vertical direction; and 
 a crack sensor configured to detect a crack in the semiconductor body, wherein the crack sensor extends into the semiconductor body, and wherein a distance between the crack sensor and the bottom side is less than the thickness of the semiconductor body; 
   specifying a first value of a characteristic variable of the crack sensor;   determining a second value of the characteristic variable of the crack sensor at a different time than the first value is specified; and   determining the semiconductor body has a crack if the second value differs from the first value by more than a pre-defined difference.   
     
     
         2 . The method of  claim 1 , wherein:
 the provided semiconductor component comprises a first main electrode pad arranged on the semiconductor body, and a connection line electrically connecting the first main electrode pad and the first crack sensor electrode pad; and   specifying the first value takes place in a state in which the connection line electrically connects the first main electrode pad and the first crack sensor electrode pad,   the method further comprising:
 interrupting the connection line by fusing. 
   
     
     
         3 . The method of  claim 2 , wherein the connection line is a thin bonding wire. 
     
     
         4 . The method of  claim 2 , wherein the first main electrode pad, the first crack sensor electrode pad and the connection line are, prior to interrupting the connection line, parts of a path-connected electrode layer. 
     
     
         5 . The method of  claim 1 , wherein specifying the first value comprises measuring the first value at the first point of time. 
     
     
         6 . The method of  claim 1 , wherein specifying the first value comprises calculating the first value based on the structure of the semiconductor component. 
     
     
         7 . The method of  claim 1 , wherein specifying the first value comprises determining the first value based on comparative measurements of one or more values of the respective characteristic variable of faultless crack sensors of semiconductor components that are identical to the provided semiconductor component. 
     
     
         8 . The method of  claim 1 , wherein providing the semiconductor component includes providing a semiconductor wafer comprising the semiconductor component, the method further comprising:
 singulating the semiconductor component from the semiconductor wafer;   specifying the first value takes place prior to singulating the semiconductor component from the semiconductor wafer; and   determining the second value takes place subsequent to singulating the semiconductor component from the semiconductor wafer.   
     
     
         9 . The method of  claim 1 , wherein the crack sensor comprises a pn-junction formed between a first diode zone and a second diode zone, and wherein the characteristic variable is a leakage current of the pn-junction. 
     
     
         10 . The method of  claim 1 , wherein the crack sensor comprises a resistance region made of a resistive material and a dielectric arranged between the resistance region and the semiconductor body, and wherein the characteristic variable is a resistance of the resistance sensor. 
     
     
         11 . The method of  claim 10 , wherein the crack sensor is partially or completely arranged in a trench formed in the semiconductor body. 
     
     
         12 . The method of  claim 1 , further comprising:
 providing an evaluation unit configured to:
 measure a value of the characteristic variable; and 
 determine, based on the measured value, a probability for a crack in the semiconductor body; and 
 one or both of:
 switch the semiconductor component in a pre-defined state if the determined probability exceeds a pre-defined limit; and 
 output a warning signal if the determined probability exceeds a pre-defined limit. 
 
   
     
     
         13 . The method of  claim 1 , wherein the crack sensor is partially or completely arranged in a trench formed in the semiconductor body.